Re MKG Post: #258949I followed your marrow rum recipe to the letter and have just filled up my demijohn with the liquid but it will only take 1/2kg of sugar. How on earth did you manage 2kg? I am getting just a little bubble but not as much as I wanted it to, obviously because there isn't enough sugar. What should I do now?

This is quite fascinating. As an amateur /home wine and mead maker "marrow rum" looks like a folk way of making a country wine from marrows. Rather than using cultured yeast you allow wild yeast/bacteria to ferment the "must" or juice from the vegetable and the juice (and not water) is the liquid that allows the yeast to transport the sugars in both the vegetable and the brown sugar through the cell walls of the yeast to allow it to convert the sugars into carbon dioxide (the bubbling gas) and alcohol. Since you are not adding water the syrup will be very dense and the density of the syrup will suggest a wine with potentially a very high alcohol content. Now, typically, yeast need nitrogen and other minerals to build and repair their cell walls and the addition of raisins might provide for some of that. I don't know what minerals are in marrows so it is possible that marrows are rich enough in the sort of chemicals that yeast need BUT I don't know that you can find marrows spontaneously fermenting so I would be a little skeptical about that. Not sure I have ever seen "marrows" in markets here in upstate NY but I have seen large summer squashes (courgettes or zucchinis) and this thread has inspired me to see what a wine made from courgettes might taste like using more .. um.. conventional practices.

A more 'conventional' approach might be to take, say 2 kilo of squash and chop them up. To the squash I would add, say 1 kilo of brown sugar and a little water - say, 2 liters. I would add yeast nutrient (which COULD be - boiled bread yeast, nutritional yeast, or even marmite. There are also lab produced nutrients designed for wine making - for example Fermaid O ) and I would add some wine or beer yeast. I would be looking for a specific gravity of about 1.090 which suggests a wine with a potential level of alcohol of about 12% ABV, so I may need to add a little more water, but I would be looking for a volume of liquid of about 4 liters. This I would allow to ferment in a cloth covered bucket for about 2 weeks or until the specific gravity had dropped to about 1.000 and then I would rack (or transfer by siphoning) the wine off the vegetable and into a clean carboy sealed with a bung and airlock where it would quietly sit for three to six months, to be racked whenever there was a few millimeters of sediment forming on the bottom of the carboy.